In arsenic contaminated areas of the Ganga-Meghna-Brahmaputra (GMB) plain (area 569 749 sq. km; population over 500 million) where traditionally cow dung cake is used as a fuel in unventilated ovens for cooking purposes, people are simply exposed to 1859.2 ng arsenic per day through direct inhalation, of which 464.8 ng could be absorbed in respiratory tract. © The Royal Society of Chemistry.